This section provides background information related to the present disclosure which is not necessarily prior art. Heat exchangers may be used to cool liquids that are continuously circulated through heat generating devices on a vehicle. For example, a vehicle air-conditioning system may compress a refrigerant, which is then cooled by passing through a multi-cooler.
The rate at which heating and cooling occurs depends upon the temperature, flow rate, and quantity of heat of incoming liquid supplied into and through the material of the heat exchanger relative to the temperature and rate of change of the temperature of external airflow. While external airflow may be delivered to the heat exchanger through either natural flow and/or with the assistance of a fan, the material of the heat exchanger may still increase in temperature over time. Additionally, certain heat exchangers experience internal temperature differentials related to their specific operation. For example, during operation of a multi-cooler the temperature of an oil cooler reaches a much higher temperature than that of a condenser. This higher temperature translates to higher thermal expansion in the oil cooler.
Thermal stress occurs as a result of expansion and contraction of the material of the heat exchanger during heating and cooling cycles with respect to constrained locations. For example, the multi-cooler experiences thermal stress in a header plate at locations between the oil cooler and the condenser.
A post-braze saw cut in the header plate of the multi-cooler may alleviate thermal stresses by allowing unrestrained expansion between the two portions; however, such a post-braze saw cut reduces stiffness in the multi-cooler. Current designs incorporate multiple brackets or complex-shaped brackets. What is needed, then, is a structure for reintroducing stiffness to the multi-cooler to stabilize against vibration, while providing a cost savings and a less complex design compared to current designs.